Thermoelectric safety device



Aug. S, 1944., H A, MAN-r2 2,355,227 v THERMOELECTRIC SAFETY DEVI CE Original Filed Jan. 8, 1937 Patented Aug. y8, 1944 v 2,355,227 THERMOELECTRIC SAFETY DEVI@ Harold A'. Manta, Milwaukee, Wis., assignor to y Milwaukee Gas Specialty Gompany, Milwaukee, Wis., a corporation of Wisconsin s claims. (ci. '17a-i7) This invention relates to thernioelectric safety devices for heating and other apparatus, and has particular relation to an imprpved thermocouple lead connector.

The present application tis a division of my copending application, "Serial No. 119,557, filed January 8, 1937, now Patent No. 2,271,506.

One of the main objects of the present invention is to provide an improved thermocouple lead connector which is adapted to provide a quick detachable connection between the lead conductors of the thermocouple and the thermoelectric safety device.

The chief advantage of the improved quick detachable thermocouple lead connector of the present invention is its ability to permit the thermocouple and lead conductors to be quickly and conveniently detached from and attached to the thermoelectric safety device. The quick detachable connection thus afforded permits the thermocouple and lead conductors to be detached and shipped disconnected or separately from the thermoelectric safety device, and it permits replacement of the thermocouple and lead conductors without returning the entire thermoelectric safety device to the manufacturer. Moreover, thermocouples with lead conductors of different lengths may be readily interchanged, and where, for instance, a, thermoelectric safety device is shipped to a user with a thermocouple having lead conductors which are not of the proper length, the thermocouple and its lead conductors may be returned in exchange for a thermocouple having lead conductorsl of the proper length without returning the entire thermoelectric safety device.

It is also an object` of the invention to provide a quick detachable thermocouple lead connector of relatively simple and inexpensive construction, and which is composed of few parts adapted for convenient assembly; also, an improved thermocouple lead connectoradapted to be quickly and conveniently detached from and attached to the thermoelectric safety device. and adapted, when attached, to provide a good thermoelectric connection between the thermocouple lead conductors and the connected device.

Another object of the invention is to provide improved fuel supply means through the wall of the housing of the device and the attaching member, and, more particularly, improved fuel supply means separated Vfrom the connector means through which the thermoelectric circuit between the lead conductor for the thermoelectric the electromagnet is completed.

Further objects and advantages of the invention will appear from the following detailed description taken in connection with the accompanying drawing, in which:

Figure 1 is a diagrammatic view showing the application of the present invention to heating apparatus;

Figure 2 is a sectional view through the device of the present invention, including the combined thermocouple and'pilot head construction; and

Figure 3 shows a modied arrangement for connecting the thermoelectric-generator and the fuel supply pipe for the pilot burner to the device.

Referring now in detail to the drawing, in Figure 1 I have shown the main fuel` supply llne 5 having the safety device 6 mounted therein and communicating through the conduit I from the outlet side of the safety `device with a fuel supply manifold or the like indicated at 8. provided with the usual gas cock 9, which may be either manually or automatically operated, for delivering fuel under pressure to the main burner I0.

The burner I0 is preferably ignited by means of a lighter tube I2 which extends into the torch head i3 receiving the pilot head indicated generally at I4. In the embodiment of the invention shown in Figure 1, the device has been shown as applied to a gas range in which a number of burners Ill may be mounted symmetrically about the torch head I3, each being supplied with a lighter tube I2 whereby gas from the main burner I0 isv transmitted through an auxiliary port and the tube I2 to the pilot burner, is there ignited, and flashes back to the burner to ignite the main burner' ports. However, it is to be understood that the torch head I3 and lighter tubes I2 may be eliminated, and in such case the pilot burner I6 may be disposed directly adjacent the main burner I0, where only a single burner is employed, such as .in hot water heaters or other types of heating apparatus.v

Considering now in detail the specic construcper portion of the valve body il is a housing 28, which may be bolted thereto as indicated by the cap screws 22 or may be secured thereto in any other suitable or desired manner. interposed between the housing 28, which is preferably oi' inverted cup shape. and the annular shoulder 28 of the valve body Il is 'a gasket member 24 which seals the surfaces that are'clamped togethenand is lprovided with an axially extending flange portion 24' at its inner periphery.

Mounted in the passage formed between the valve body I and the housing 28 is a magnetic frame member 28 having the electromagnetic coil 28 carried therein, the coil 28 having one terminal thereof grounded to the housing 2li, as indicated at 21, throughvthe conductor 28, and having its opposite terminal connected through conductor 28 to a terminal thimble 88 which. is disposed in insulated relation to the housing by being carried within the insulating bushing 82. 'I'he magnet frame 2l is provided with a central axially extending recess 88 which is adapted to receive a spring member 84 biased at one end against the inner end of the recess 88,*and at its opposite end bearing against the turned over edge 85 of the projecting stem portion 85 of valve member 81, the member 81 in turn carrying at its lower base the leather valve seating member 88 adapted to have engagement with the valve seat I8. lThe leather seating member is held in position by the retaining washer or disc 88 which, in turn, is secured to the member 31 by means of the threaded plug 48 extending into the open end of the recess 42 formed in the member.

A suitable valve stem 48 is carried within the recess 42 o! the member 81, and normally is pressed into seating engagement with the valve seat 44 by means of the spring 45 encircling the valve stem and biased at its lower end against the packing carried in the upper end of the recess 42.

The member 81 is provided with a laterally extending port 48 which extends into and communicates with the passageway 42 above the valve stem head 41. The member 81 is also provided with a second axially offset laterally extending communicates through the passageway 48 directed axially of the valve member and through the valve member 88 with the lower radial face of the valve member 88.

The valve seat I8 is provided with a passageway -50 opening at one end therethrough and there adapted to be aligned with the passageway 49. Passageway 58 is of substantially L- shape and opens at its other end into a passageway 52 extending upwardly through the valve body to the gasket 24. The gasket 24 is apertu-ed, as indicated at 52, providing communication between the passageway 52 and a corresponding passageway 54 extending through only one side wall of the housing 28 and through the insulating bushing 82 into the interior of the thimble Il, which thimble is provided with an axially outwardly directed recess 58 which opens outwardly through the threaded boss portion 51 extending laterally from the side ot the housing 28. 4

, The valve member 81 forms, wgether with the cup-shaped member 80 and the annular plate member 82, an armature-like Yvalve member which is movable toward and away from the lower end of the magnet frame 25, having sliding' movement guided by the axially extending flange portion 24' of the gasket 24. Thus, when the coil 28 is deenergized, the spring I4 urges 'the armature, consisting of the members 88, 82 and 81, downwardly away from the lower end of the magnet frame and into engagement with the valve seat i8. f f f 'I'he magnetic frame 25 is normally retained I in position within the safety device by means o! g the spindle member 85 which has the head porm tion 88 engaged'within the recess 88 of the armature frame and which extends upwardly and carries at its'outer end the resetting button 81, which is threaded to the end of the spindle 8l and is recessed to receive one end of the spring l5 88, the opposite end of the spring 88 `bearing against packing 68 carried within the recessed portion 18 or extending downwardly into the housing 28 and formed integral therewith. 'I'he l spring 88 normally urges the button 81 outwardly of the housing 28 and thereby urges the spindle 85 upwardly, holding the magnetic frame 25 against the lower end of the wall portion 12 of the housing which denes the recess 10.

.Considering now in detail the pilot burner construction, this comprises an outer tubular member 80 which is provided with relatively large open ports 82 through which pilot flames 88 are adapted to project, as indicated diagrammatically in Figure 2, and which is joined to an inner tubular member 84, there being a. welded junction between these two members as indicated at 85 forming a thermocouple junction disposed in the path of the pilot flames 83. The inner tubular member 84 is provided with a plurality of ports 4 88 of reduced area as compared to the ports 82, and Ais connected, at its open end, through the bushing 81 with a hollow metallic conduit 88 which extends to the thermocouple and burner connection indicated generally at 88 whereby the burner and thermocouple are connected to the safety device 8. The lower end `of the outer member 88 is 'supported by a spider-likev member l82 which is provided with openings 83 there- 'in for admitting air into the spacebetween the f members 88 and 84, this air merging with the gas issuing from the ports 86 to produce the burner flame 83. Suitable insulation 84 is provided between the inner metallic structure 88 and the outer metal tube 95 which terminates in the spider 82. It will thus be seen that a thermocouple junction is provided at 85 and that one terminal of this junction is connected through the outer cylindrical member 80 and the metal tube as to the thimble 9s which is threaded over the threaded extension 51 of the housing 20 and thereby completes a connection to the grounded. terminal 21 from one side of the coil 28. The other side ot the thermocouple circuit extends from the inner tubular member 84 and the metal conduit member 88, within the insulating sleeve s4, to the recess 58 formed in the thimble 80. This makes metallic contact through the thimble 30 with the conductor 29 leading from the other side of the magnetic coil 28.

An insulating disc 98 is disposed about the projecting end of the conduit 88 within the thimble 88, and a wedge-shaped member 88, preierably of ductile metal, is disposed over the projecting end of the conduit 88 whereby, 'upon threading of the thimble 86 upon the extension 51, the wedge member 88 is wedged, together with the projecting end of the conduit 88, into the recess 58 of the thimble 30, and consequently lforms a positive and gas tight electrical connection therewith which is insulated from the metal tube 66 and from the supporting sleeve I0( disposed Within the thimble 88. If desired, the

`metal tube 35 may be provided with a riding wipe or enlargement |02 with which the thimble 96 may engage at its reduced end in order to move the entire structure as a unit inwardly with respect to the thimble 30 when the thimble is tightened over the extension on the housing 20.

This' provides a quick detachable connection not requiring the unloosening of any terminal screws, terminal lugs or the like. since by merely untreading the thimble 96 the connection -between the conduit 88 and the thimble 3|) may be readily broken and the entire pilot burner and thermocouple structure may be removed from the safety device 6.

In the operation of the device as thus far described, the device is shown in Figure 2 as being in valve opened position, with the pilot ame through passageways 62and 84 and into the recess 56 in the terminal bushing 30. From this recess. gas is passed through the hollow c'onductor 88 to their interior of the tubular member 84, from which it escapes through ports 66 and mixes with -air introduced into the interior of the tubular member 60, and can be ignited, as it issues with the air from the ports 82. The resulting pilot flames serve to energize the thermocouple, creating la current which in turn energizes the coil 26 and causes the. armature formed by the members '60, 62 and-31 of the valve ignitedand the magnetic coil 26 thereby en- A ergized to hold the armature including the valve member 31 to the magnet frame against the resistance of the spring 34. This is due to the fact that the heat of the pilot name acting on welded junction 85 creates a current flow between the metal tube 95 and the hollow conduit 68 which, in turn, creates a ow of current through the coil 26 sufficient to magnetize the magnet frame 26 and create an attractive force on the valve member 31 sumcient to hold it against the magnet frame. Consider now that theV pilot llame is accidentally extinguished. The thermocouple junction rapidly cools and thereby deenergizes the coil 26. The spring 34 thereupon becomes active and snaps the valve member 31 downwardly into engagement with the valve seat I3. This results in relative sliding engagement of the cup-shaped member 60 with respect to the gasket portion 24' of the gasket 24 while the magnetic frame and the coil 26 remain in iixed position due to the eiect of the spring 68. The valve is therefore closed, closing .off communication between the inlet chamber I6 and thev outlet chamber I1', and also closing off the fuel supply to the pilot burner. This latter fuel supply is closed oi due to the fact th-atvthe spring 45 retains the valve stem 43 in position with the head 41 thereof pressed againstthe valve seat 44 so that no gas may ow from the inlet chamber I6 through the passageways 46, 48 and 49 to the passageway 50. n

When it is desired to either ignite the main burner or to reignite the pilot burner, the resetting button 61 is manually pushed downwardly. This results in moving the spindle 65 downwardly with respect to the magnet frame 25, and the magnet frame thereby slides downwardly within the upper end of the cup-shaped member 60 due to the fact that the shoulder |04 of the spindle 65 engages the top of the magnet frame and forces it downwardly against the pressure of spring 34. At the same time, the head end 66 of the spindle 65 engages the upper end of the valve stem 43, forcing the valve 41 away from its seat 44, and thereby opening communication between the passageways 46 and 48 formed in the valve member 31. 4

As a result, the gas which is under pressure in the inlet chamber I6 ows through the passageways .46 and 48 and thence through the axially extending passageway 49 into the passageway 50 formed in the valve seat I9. From construction to be held positively against the lower end of the frame 25 by magnetic attraction. As a result, when the reset button 61 is released, the spring 68 moves the button 61 and spindle 65 upwardly, which in turn, through. the head end 66 of the spindle 66, moves the frame 25 upwardly and consequently moves the valve member therewith, the two being held in magnetic attraction. This opens the valve, and the gas may then flow from the inlet chamber I6 through the valve seat I9 into the outlet chamber I1 and thence to the main burner or burners. At the same time, suiilcient gas is still supplied through the port in the valve seat to maintain the pilot burner I4 ignited, and cori-- sequently retain the valve member in raised position against the lower end of the magnet frame 26. Upon any accidental extinguishment of the pilot burner, the magnet is immediately deenergized, and the spring 34 `consequently forces the valve member down into engagement with the valve seat, thereby shutting oil' ilow of fuel to either the pilot burner or the main burner.

In Figure 3 I have shown a modified construction in which the supply for the .pilot burner is separated from the connection to the thermocouple junction. In this embodiment of the invention, the valve body isindicated at |30, while the housing for the magnetic frame and reset mechanism is indicated at |32, the two lbeing secured together with the gasket |33 interposed A opens outwardly through the attaching member to the housing |32 by means of the :cap screw` |39 threaded to the side wall of the housing; The connection for the coil 26 is provided by the conductor |40 which extends into the metallic thimble |42 secured within the insulating 'bushing |43 and joined to the conductor |44 extending to the thermocouple junction by means of the tubular metallic coupling member |45, which seats in thimble |42 and in a second similar metallic thimble in the attaching member |31, as shown. Suitable insulation |46 extends about the conductor |44 and into the attaching member |31, forming a continuation of the insulating bushing |43. Communication between recess |36 and the conduit |38 is afforded by a second tubular coupling member similar to member |45,

seating in the wall of thevalve body |30 and in the attaching member |31, the latter having a port opening into the coupling member and the adjacent end of conduit |38, as shown.

As far as the operation of the device, or the energization of the coil 26 and the supply of fuel tothe pilot burner, is concerned, the mechanism the passageway 50, this gas ows upwardly 76 shown in Figure 3 will operate in the same manner as described in connection with Figure 2,

f4 asomar and no further description of the operation'thereof is deemed necessary. I

lIt is therefore believed apparent that I have provideda novel type of safety device in which the magnet i'rame is reciprocally mounted in the housing for the safety device and is moved downwardly into engagement. with the valve member in order to pick up the valve member when the magnet has been energized and move it into valve open position. At the same time, whenever the pilot llame is accidentally extinguished, the supply oi fuel to both the main burner and the pilot burner is automatically shut oil, and when the resetting means is actuated, a limited supply of fuel to the pilot burner is .provided without opening the main valve until 'such time as the pilot burner has been ignited and a sui!- ilcient current has been generated to allow actuation of the magnet. Further, Ivhave provided means i'or rapidly attaching .and disconnecting the thermocouple and pilot burner connections, which facilitates assembly of the deviceand insures easy replacement or repair in case ot damage or for inspection.

I am aware that various modiilcations may be made in details ot structure and particular de sign, and intend that the illustrated embodiment of the invention be considered for purposes of illustration only as showing one form -of the invention. I do not intend to limit my invention to the exact details shown, but only in so far as defined by the scope and spirit of the appended claims.

I claim:

1. In connector means of the character described, -a wall structure having therein a recess opening through one face thereof and a passage opening into said recess, a ilrst metallic thimble mounted in and insulated from said Wall structure and spaced from said recess, an attaching member ex-tending between and overlying said recess and said thimble, a second metallic thimble mounted in and insulated from said attaching member in alignment with said nrst thimble,

lead conductors respectively connected to saidA thimbles, a hollow conduit secured at one end in said attaching member. the latter having a port therein open at one end to the adjacent end of said conduit, a metallic coupling member seating at its ends in said `thiinbles, g tubular coupling member seating at its ends in said wall structure at the outer end of said recess and in said attaching member at the other end of said port thereof, and means for securing said attaching member to and forcing it toward said wall v structure eilective for clamping said coupling members in position.

2. In connector means of the character described, a wall structure having therein a recess opening through one face thereof intended for connection to a source of supply oi iluida nrst metallic thimble mounted ,in and insulated from saidwall structure and spaced from said recess, an attaching member extending between and overlying said recess and said thimble, a second metallicthimble mounted in and ins ted from said attaching membery in alignment with said first thimble, lead conductors respectively connected to said thimbles, a hollow conduit secured to said attaching member, means for securing said *attaching member to and forcing it toward said wall structure, a metallic coupling member clamped between said thimbles, and means establishing communication between said recess and said conduit comprising a tubular coupling member clamped between said wall structure and said attaching member.

3. In connector means oi' the character described, a wall structure, an attaching member, means for securing said member to and forcing it'toward said wall structure, lead conductors respectively carried by and insulated from said wall structure and said member, a hollow conduit secured to said member and spaced from the lead conductor carried thereby. means electrically connecting said lead conductors comprising a coupling member clamped between said attaching member and said wall structure, and a tubular coupling member clamped between said attaching member and said wall structure, the latter and said attaching member having cooperating means for connecting said conduit through said tubular coupling member to a source of supply of iluid.

HAROLD A. MANTZ. 

